Sheffield Industries has adopted the following production budget for the first 4 months of 2022. Month Units Month Units January February 12,600 March 6,300 10,080 April 5,040 Each unit requires 2 pounds of raw materials costing $3 per pound. On December 31, 2021. the ending raw materials inventory was 5,040 pounds. Management wants to have a raw materials inventory at the end of the month equal to 20% of next month's production requirements. Prepare a direct materials purchases budget by month for the first quarter.